The county’s public health department issued an advisory for Wednesday suggesting that schoolchildren be kept indoors as much as possible, and that pregnant women minimize smoke exposure as well. People have been advised to avoid exercising outdoors until the smoke clears.

On Wednesday, those suffering from lung or heart disease within 50 miles of the fire were told to evacuate to areas outside that perimeter. And those with pre-existing respiratory conditions were told to expect symptoms like coughing, shortness of breath, chest discomfort and shortness of breath.

The county advised those who can smell smoke to stay inside if possible.

Even veterinarians were suggesting that pet owners treat dogs and cats like people, keeping them indoors. Especially if they have pre-existing respiratory problems.

“If you or I can get affected by smoke, animals can in the same way,” says veterinarian Clint Kay of the South Boulder Animal Hospital.

Kay says his clinic has only seen a few dogs and cats in the last few days that have been having problems with wheezing or coughing.

Lee Woods, a vet at the Broadway Animal Hospital, on the other hand, says he is not attributing any of the pet ailments he’s seen this week to the smoke, but his facility’s boarding areas are nearly filled, and regular clients are being solicited to act as foster homes for animals.

Like people, Woods says, pets’ outdoor exercise should be limited, because the smoke can contain chemicals like hydrogen cyanide, from household materials being burned.

“It’s probably not a good time to do extended mountain biking or exercising,” he says.

Smoke from the fire is dangerous, particularly to the elderly and children,
says Jose Luis Jimenez, an air pollution researcher at the University
of Colorado’s Cooperative Institute for Research in Environmental
Sciences.

He says that for people with preexisting cardio-respiratory ailments, “it may push them over the edge.”

Jimenez
says it’s well documented that mortality rates increase during high
pollution and events like forest fires. But this fire, he says, is not
the sort of event that is likely to trigger such an increase in
mortality.

“I’m not
a doctor, but I personally think that right now only people who are
particularly susceptible should leave,” says Jimenez. “If it gets thick
again, it’s better for people to not be in it.”

Randy
Bjerke, a pulmonary disease specialist at Boulder Community Hospital,
suggests running air conditioning or other air-circulation systems in
the home, since they usually have filters that can help counter the
smoke’s effects. He also says those who have pre-existing conditions may
want to wear simple painter’s masks if they have to go outside.
According to Bjerke, higher-end carbon filter

masks are not necessary, since they are intended to protect against gases.

But he says people should just use common sense, and that conditions differ across the county.

“I live in north Boulder, and it’s been brutal,” Bjerke says. “We couldn’t see the sun, we couldn’t see anything.”

He adds that exercise only exacerbates the effects of the smoke.

“You
may be taking in five or 10 times as much as when you’re sedentary,”
Bjerke explains. “Go to a rec center, do something indoors for a few
days. … It’s just common sense to protect yourself for what we hope is
only the few days needed to knock this back.”

He
notes that he and his partners at BCH have not treated any healthy
people for smoke-related complications yet this week, although a few
emphysema patients have been admitted.

“If
you get a fever or start coughing up colored mucous, get that checked,”
Bjerke says, adding that his own throat has been sore in the mornings.
“But just a scratchy throat is not enough to get treated.”